Figure 2

Selenium reduces thrips herbivory to A. bisulcatus in both choice and non-choice experiments. A-C: Thrips non-choice feeding experiment where thrips were offered only high-Se or low-Se plants. Herbivory was quantified as the percentage of entire A. bisulcatus young, medium and old leaves that showed herbivory (A) and as the percentage of leaflets per leaf that showed herbivory (B). The leaf Se concentration of the high-Se and low-Se plants used in the non-choice studies is shown in panel C. D-F: Thrips choice feeding experiments where thrips were provided with a choice between high-Se and low-Se plants. Herbivory was quantified as the percentage of A. bisulcatus young, medium and old leaves that showed herbivory (D) and as the percentage of leaflets per leaf (E) that suffered herbivory. The leaf Se concentration of the plants used in the choice study is shown in panel F. Values are means +/- SE. An asterisk above a pair of bars represents a significant difference between the high-Se and low-Se treatments (t-tests, α = 0.05, n = 6 for both high-Se and low-Se non-choice experiments, n = 4 for choice experiments).